Sirindhorn International Institute of Technology

About: Sirindhorn International Institute of Technology is a based out in . It is known for research contribution in the topics: Supply chain & Combustion. The organization has 1048 authors who have published 1678 publications receiving 30067 citations.

Model for Simulating Carbonation of Fly Ash Concrete

Abstract: The aim of this paper is to develop a model for simulating carbonation of fly ash concrete. The model describes the diffusion of gases ( C O2 and water vapor) in concrete by the mass balance equations and the Fick’s law of diffusion. The time dependent hydration, and pozzolanic and carbonation reactions were considered for evaluating the amount of calcium hydroxide in concrete. The rate of carbonation reaction was formulated based on the Arrhenius’s formulation. The model was verified by using the results of relative water content, amount of calcium hydroxide, and carbonation depth tested in accelerated and real environments. The influence of changes in parameters on mix proportion and environmental condition were investigated. The verification results were found to be satisfactory in the prediction of carbonation of fly ash concrete.

Tensile behavior of restrained expansive mortar and concrete

Abstract: Effect of restraint on the tensile behavior of expansive mortar was investigated by testing specimens with concentrically un-bonded restraint, chemically prestressed mortar (CPM), and chemically prestressed concrete (CPC). The deformation under flexural load is measured by a series of strain gages. In the test of specimens with un-bonded restraint, the restraining steel was removed and the expansion, chemical prestress, and rebound strain are measured before the flexural test. Tensile strength, cracking strain capacity as well as the plastic deformation was quantitatively investigated. The results show that the restrained expansive mortar has unique tensile properties, i.e., larger cracking strain capacity, non-linearity, and more plastic deformation. The effects of bonding between rebar and mortar, curvature, and the presence of coarse aggregate on the tensile properties of CPM and CPC were also experimentally investigated.

Automatic acne detection for medical treatment

Abstract: In this paper, an effective image processing technique has been studied to develop a system of acne detection. The focus is on binary thresholding applied to facial images with various types, shapes or amounts of acne. A typical image on a cheek has been usually used to take in the experiment which results are markings on acnes automatically, this method is more effective than manual counting by a typical dermatologist. An input image is first taken into gray and special color model from regular red-green-blue version, this work is for comparison and revelation of region of interest. The regions of interest are mostly acnes but it can contain some noise. Then binary threshold has been used to clearly show and can remove the noise easier from regions of acne. A box shape is constructed to mark the final result of acne detection, so that correct and incorrect detected acne can be displayed and calculated for a system efficiency. Experimental output can be summarized that accuracy, precision and sensitivity are quite fluctuated depending on color, shape and lighting condition of acnes in the image.

Learning Proxemics for Personalized Human–Robot Social Interaction

Abstract: Each person has their personal area which they do not want to share with others during social interactions. The size of this area usually depends on various factors such as their culture, personal traits, and acquaintanceship. The same applies to the case of human–robot interaction, especially when the robot is required to exhibit a certain level of social competence. Here, we propose a new robot navigation strategy to socially interact with people reflecting upon the social relationship between the robot and each person. To this end, we need a clear definition of interaction areas: (1) quality interaction area where people can be engaged in high-quality interactions with robots, and (2) private area not to be interfered with by the robot speech or action. A technical challenge in enhancing social human–robot interactions is how to enable robots to delineate the boundary of the two areas of each person. Specifically, the social force model (SFM) is designed by a fuzzy inference system, where the membership functions are optimized to give the robot the ability to navigate autonomously in the quality interaction area using a reinforcement learning algorithm. Finally, the proposed model was verified through simulations and experiments with a real robot that can generate a suitable SFM of each person, allowing the robot to maintain the quality of interaction with each person while keeping their private personal distance.

Investigation of factors affecting a construction waste recycling decision

Abstract: The production of high amounts of construction waste is a serious problem in many large cities. Ineffective waste management leads to environmental, health, and safety problems. This paper examines key factors influencing construction waste recycling decisions, utilising the exploratory factor analysis approach and the analytic hierarchy process (AHP). A questionnaire was used to extract key factors and subfactors of construction waste recycling. The analysis of the 107 data sets (27% of the total questionnaires sent) extracted three key factors, namely Economics, Market and Site Activities, and Environment factors. The AHP was then performed using experts’ interviews. The results revealed that the Market and Site Activities factor was the most influential factor in making waste recycling decisions, as it has the highest weight among the three factors. Critical issues of concern were the amount of recycled markets available and the intense competition in the industry. Apart from that, high cost of...